B1666
Title: Optimal repetitive reliability inspection of manufactured lots for lifetime models using prior information
Authors: Carlos Perez-Gonzalez - Universidad de La Laguna (Spain) [presenting]
Arturo J Fernandez - Universidad de La Laguna (Spain)
Vicent Giner-Bosch - Universidad Politecnica de Valencia (Spain)
Andres Carrion-Garcia - Universidad Politecnica de Valencia (Spain)
Abstract: Repetitive group inspection of production lots is considered to develop the failure-censored plan with minimal expected sampling effort using prior information. Optimal reliability test plans are derived for the family of log-location and scale lifetime distributions, whereas a generalized beta distribution is assumed to model the nonconforming proportion, $p$. A highly efficient and quick step-by-step algorithm is determined in order to solve the underlying mixed nonlinear programming problem. Conventional repetitive group plans are often very effective in reducing the average sample number with respect to other inspection schemes, but sample sizes may increase under certain conditions such as high censoring. The inclusion of previous knowledge from past empirical results contributes to reducing drastically the amount of sampling required in life testing. Moreover, the use of expected sampling risks improves significantly the assessment of the real producer and consumer sampling risks. Several tables and figures are presented to analyze the effect of the available prior evidence about $p$. The results show that the proposed lot inspection scheme clearly outperforms the standard repetitive group plans obtained under the traditional approach based on conventional risks. Finally, an application to the manufacture of integrated circuits is included for illustrative purposes.
